<div>3.3 Opposing Changes in Rainfall Properties: Increased Conditional Rain
Rates, Decreased Duration and Areal Coverage</div><div>Changes in the event-based areal mean rainfall accumulation are examined
through changes in three rainfall components: mean conditional rain
rate, event duration, and rain area (Fig. 5, Fig. S4-S5). The mean
conditional rain rate significantly increases with an average change of
15%, and &gt;85% of the events show higher average
conditional rain rate in the future compared with the historic
simulations. Although there is some correlation between the changes in
mean conditional rain rate and total rainfall (Spearman’s correlation:<span class="ltx_Math math v1">\(\rho=0.37\)</span>; Fig. S5) increases as large as 47% (event #16) are
observed in events with a reduction of the rainfall accumulation. This
suggests that the change in the mean conditional rain is rather weakly
related to rainfall accumulation.</div><div>While mean conditional rain rate is increasing, the duration of events
shows a significant negative change (-9%), from a mean of 3290 min to
2980 min, and &gt;75% of the events are longer in historic
compared to future simulations (Table 1). The reduction in durations is
not, however, a good predictor for the reduction in total rainfall
accumulation, with a low, non-significant negative correlation between
the two (Fig. S5).</div><div>The third component in this analysis, the rain area, reveals the largest
relative change out of all three components. It also presents the
highest correlation with the change in rainfall accumulation
(<span class="ltx_Math math v1">\(\rho=0.93\)</span>; Fig. S5). The rain area is decreased in all but one of
the events (&gt;97% of events) with a significant and
substantial average decrease (-40%). Events with the lowest reduction
(or even slight increase) in rainfall accumulation are only those in
which the reduction in the rain area is relatively small, while events
with a large decrease in rainfall accumulation are accompanied by a
large decrease in rain area. These results indicate that the factor most
heavily related to changes in rainfall accumulation is the rain area.</div>